1. Field of the Invention
The present invention relates generally to a needle shielding device for use in reducing the risk of inadvertent needle strikes of both a patient and a person administering an injection or drawing blood from the patient.
2. Description of the Prior Art
Medical professionals are susceptible to accidental needle strikes during the administration of medicines to, or when drawing blood from, a patient. There exists an increasing concern for the potential transmission of infectious diseases, such as AIDS and hepatitis, through exposure to accidental needle strikes. To combat the spread of disease, there have been numerous attempts to devise needle shielding devices intended to reduce the risk of accidental needle strikes. For example, a sheath is disclosed in U.S. Pat. No. 2,571,653, issued Oct. 16, 1951 to Victor G. Bastien. The sheath is operable between an extended position and a retracted position, and is cooperatively engageable with the barrel of a syringe to lock in each position. An annular opening is provided at each end of the sheath. When the sheath is in the retracted position, the needle is extendable through one opening and the barrel is received by the other opening.
Another needle shielding device is shown in U.S. Pat. No. 4,356,822, issued Nov. 2, 1982 to Deborah Winstead-Hall. Winstead-Hall discloses a cap which receives at least a portion of the barrel of a syringe. The cap includes locking members for securing the cap and barrel in a number of relative positions.
U.S. Pat. No. 4,631,057, issued Dec. 23, 1986 to Charles B. Mitchell, discloses yet another needle shielding device. This needle shield device is mounted on the barrel of a syringe and is movable relative to the barrel from a retracted position to an extended position. An annular rib engages the barrel to maintain the shielding device in a retracted position. Upon extension of the shielding device, a pair of teeth engage the barrel to lock the shield in an extended position.
A shielding device is disclosed in U.S. Pat. No. 4,826,491, issued May 2, 1989 to James J. Schramm, wherein the shield includes teeth which cooperate with a syringe to provide three distinct retaining positions. The shield is substantially non-releasable from an extended position around the needle.
U.S. Pat. No. 4,955,868, issued Sep. 11, 1990 to Edward Klein, relates to a modification of a hypodermic syringe having a shield to cover the needle of the syringe. This shield is retractable to allow the needle to extend past the shield. A spring is used to automatically return the shield to a position covering the needle.
Shielding devices for adaptation to conventional syringes are disclosed in U.S. Pat. No. 4,998,920, issued Mar. 12, 1991 to Delores Johnson, and U.S. Pat. No. 5,106,380, issued Apr. 21, 1992 to Diane Lobello. These devices each include a collar adapted to be affixed to a syringe adjacent the syringe needle and a sleeve adapted to be arranged circumjacent the syringe barrel. These sleeves engage the collar upon placement of the sleeve in an extended position. The sleeve according to Johnson is further engageable with the collar in a retracted position.
Another shielding device for use with syringes is disclosed in U.S. Pat. No. 5,084,030, issued Jan. 28, 1992 to Phillip O. Byrne et al. The shield according to Byrne is movable from a retracted position to an extended position and is maintained in the extended position by a hidden projection that engages the syringe.
UK Patent Application GB 2 202 747 A, published Oct. 5, 1988 for William Ducat, discloses a needle shield which includes a sleeve that is axially slidable over the barrel of a syringe. The sleeve may be spring biased and lockable in position. Another needle shielding device deemed of interest is shown in an Italian publication, No. 704152, published Apr. 19, 1966 for Unberto Fonghini.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.